I popped to the lovely city of Ghent in Belgium recently to see Divinity 2 developer Larian and play the game.
Why go round the houses looking for the information you need to finish a quest when you can scoff a head and do it that way? It's Divinity: Original Sin 2 in a nutshell: a cheeky, subversive fantasy toy box that has an even bigger box of tools than the first game to play with. It's another option in a game of options.
Eating corpses is a racial ability, what elves in Divinity 2 just happen to do, and when they gobble an arm or a head or a leg they learn things about who it came from - discover secrets. Eat that Legolas! I suppose in Divinity 2 an elf literally would. In Divinity: Original Sin 2, elves eat corpses.